java - Min/Max Values of an Array

Question

I seem to be stuck on what seems to be a pretty basic assignment. I was wondering if anyone could possibly lead me to the right direction and explain to me what is wrong. I have created an array with premade values inserted. Now I have to get the min/max values of this array and display them as well. I keep getting these two errors

".java:126: error: method getMax in class HighArray cannot be applied to given types;"

".java:126: error: method getMin in class HighArray cannot be applied to given types;"

If anyone could possibly help me out and explain why this is, it would be greatly appreciated. Thank you!

class HighArray
{
    private long[] a;
    private int nElems;

    public HighArray(int max)
    {
        a = new long[max];
        nElems = 0;
    }

   //Search Method 
    public boolean find(long searchKey)
    {
        int j;
        for(j=0; j<nElems; j++)
            if(a[j] == searchKey)
                break;
        if(j == nElems)
            return false;
        else
            return true;
    }

    //Insert method     
    public void insert(long value)
    {
        a[nElems] = value;
        nElems++;
    }

    //Delete method        
    public boolean delete(long value)
    {
        int j;
        for(j=0; j<nElems; j++)
            if( value == a[j] )
                break;
        if(j==nElems)
            return false;
        else
        {
            for(int k=j; k<nElems; k++)
                a[k] = a[k+1];
            nElems--;
            return true;
        }
    }

    //Display Array Contents 
    public void display()
    {
        for(int j=0; j<nElems; j++)
            System.out.print(a[j] + " ");
        System.out.println(" ");
    }

    //Max Method 
    public static int getMax(int[] a)
    {
        int maxValue = a[0];
        for(int i=1;i < a.length;i++)
        {
            if(a[i] > maxValue)
            {
                maxValue = a[i];
                System.out.print("The max value is" + a[i]);
            }
        }
        return maxValue;
    }

    //Min Method
    public static int getMin(int[] a)
    {
        int minValue = a[0];
        for(int i=1;i<a.length;i++)
        {
            if(a[i] < minValue)
            {
                minValue = a[i];
                System.out.print("The min value is" + a[i]);
            }
        }
        return minValue;
    }
}

public class Assignment
{
    public static void main(String[] args)
    {
        int maxSize = 100;
        HighArray arr = new HighArray(maxSize);
        arr.insert(77);
        arr.insert(99);
        arr.insert(44);
        arr.insert(55);
        arr.insert(-22);
        arr.insert(88);
        arr.insert(-11);
        arr.insert(00);
        arr.insert(66);
        arr.insert(-33);

        arr.display();
        arr.getMax();
        arr.getMin();

        int searchKey = 35;
        if( arr.find(searchKey) )
            System.out.println("Found" + searchKey);
        else
            System.out.println("Can't Find " + searchKey);

        arr.delete(00);
        arr.delete(55);
        arr.delete(99);

        arr.display();
    }
}
           

Answer 1

Methods:

• public static int getMax(int[] a) and
• public static int getMin(int[] a)

have int[] as their input parameter,
but they are later called without any parameters: arr.getMax(); and arr.getMin();.

This is the cause of the error you are getting from the compiler.

EDIT:

You probably want to modify your methods not to be static and not to have any input parameters (the array a would be used directly from the object and not passed to the method), so you can use methods on the object of the class like this: arr.getMax();.

To do so change the code in the following way:

• public static int getMax(int[] a) --> public long getMax()
• public static int getMin(int[] a) --> public long getMin()

* Note: The return type of getMax and getMin methods is changed from int to long, because longis the type of array in the HighArray class.